Perception is defined as "the process by which an organism detects and interprets information from the external world by means of the sensory receptors". Of course, everyone has the ability to see things, or perceive things, differently than others.
Here in Florida, we have a lot of 55+ communities. We also don't have front license plates on our cars. Because of this, many of these areas have license plates with the name of the community on it. Now, you've just told me where you live. For example. I may see an elderly man or woman in the checkout line in front of me paying for their purchase. When they produce their cash, I may see large bundles of cash. An easy target? Maybe. As a criminal, would I have to commit my crime now? Ahh, I see you have a license plate telling me where you live. I'll just follow you and then come back to "visit" later.
People tend to be fascinated with my profession. At gatherings, discussions tend to "go there". They want to know what it's like. They have questions and they want details, some, even want pictures. Why? They have no idea of my world except by what they read in the newspapers, and even then, can't even imagine. They want to know, while at the same time, they don't. Many get visibly disturbed in the conversation. They ask me if it affects me. Of course, I tell them that I don't think about it (to be honest, I think about it all the time). I've even had one person refer to me as "being dead inside". Certainly not a compliment but that is how he perceived me.
What you see and what I see are different. You may see a cigarette butt on the ground, yet I see it as potential evidence, DNA and fingerprints. You see those "family" stickers and community license plates as nothing more than they are. I see information and vulnerability. You see a photo of a deceased victim. I see evidence and clues to solve the crime.
I view myself as being successful in my profession. Seeing the world the way I do may be considered "dark" to some people. My "rose colored glasses" were shattered many years ago. Am I dead inside? I certainly hope not. I guess that depends on your perception.